If you experience any of the following you should go to the nearest hospital emergency department as soon as possible: 1  Heavy bleeding (soaking two pads every hour and/or passing golf ball sized clots) 2  Severe abdominal pain or shoulder pain. 3  Fever or chills. 4  Dizziness or fainting. 5  Vaginal discharge that smells unpleasant.
One of the most famous emission nebulae is the Orion Nebula (M42) located just below Orionâs belt. Another common type of emission nebula is a planetary nebula. These objects consist of a central white dwarf star surrounded by clouds of gas released as the original star evolved to the white dwarf phase.
Many nebulae or stars form from the gravitational collapse of gas in the interstellar medium or ISM. As the material collapses under its own weight, massive stars may form in the center, and their ultraviolet radiation ionizes the surrounding gas, making it visible at optical wavelengths.xamples of these types of nebulae are the Rosette Nebula and the Pelican Nebula. The size of these nebulae, known as HII regions, varies depending on the size of the original cloud of gas. New stars are formed in the nebulae.